Helmert–Wolf blocking

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1	The national readjustment of all horizontal survey control is underway and expected to be completed by 2007 Add to Reading List Source URL: www.ngs.noaa.gov Language: English - Date: 2006-03-24 11:59:47 Geophysics Datum National Spatial Reference System Geodetic network Geographic coordinate system Global Positioning System Helmert–Wolf blocking Surveying Friedrich Robert Helmert Geodesy Cartography Measurement
2	NOAA Technical Report NOS NGS 60 NAD 83(NSRS2007) National Readjustment Final Report Add to Reading List Source URL: www.ngs.noaa.gov Language: English - Date: 2009-03-26 05:31:00 Geophysics Surveying Navigation Datum Helmert–Wolf blocking Friedrich Robert Helmert National Spatial Reference System Geographic coordinate system Geodetic system Geodesy Cartography Measurement